 |
 |
|
|
|
|
Title: |
US7484075:
Method and apparatus for providing fast remote register access in a clustered VLIW processor using partitioned register files
[ Derwent Title ]

|
Country: |
US United States of America

|
| |
Inventor: |
Kailas, Krishnan K.; Ossining, NY, United States of America

|
Assignee: |
International Business Machines Corporation, Armonk, NY, United States of America
other patents from INTERNATIONAL BUSINESS MACHINES CORPORATION (280070) (approx. 44,393)
News, Profiles, Stocks and More about this company

|
Published / Filed: |
2009-01-27
/ 2002-12-16

|
Application Number: |
US2002000320150

|
IPC Code: |
Advanced:
G06F 9/30;
G06F 9/38;
G06F 15/00;
G06F 15/80;
Core:
G06F 15/76;
more...

|
ECLA Code: |
G06F9/38T; G06F9/30R4S; G06F9/38D; G06F9/38D2; G06F9/38E6;

|
U.S. Class: |
712/024;

|
Field of Search: |
712/213,210,24
711/214

|
Priority Number: |
| 2002-12-16 |
US2002000320150 |

|
Abstract: |
Effective remote register file access time can be reduced in a clustered VLIW processor using partitioned register files and some additional hardware for pre-fetching remote registers. An instruction pre-fetcher and an instruction pre-decoder is used for pre-fetching and partially decoding instructions in order to pre-fetch the remote registers required for executing VLIWs at run-time, thus substantially reducing the number of inter-cluster copy instructions. The instructions (VLIWs) are scheduled taking into account the various hardware constraints such as limited inter-cluster communication bandwidth, inter-cluster communication delay, etc.

|
Attorney, Agent or Firm: |
Trepp, Robert M. ;
F.Chau & Associates, LLC ;

|
Primary / Asst. Examiners: |
Huisman, David J; Petranek, Jacob

|
INPADOC Legal Status: |
None
Family Legal Status Report

|
Family: |
Show 4 known family members

|
First Claim:
Show all 20 claims |
1. A computer system, comprising: a plurality of clustered processing cores for processing VLIW (Very Long Instruction Word) operations, wherein each processing core comprises: a local partitioned register file having a subset of an architected name space; an instruction decoder to decode a VLIW for execution; an inter-cluster communication bus enabling communication between the processing cores; a processor pipeline including a plurality of stages for operating on the VLIW; and a hardware register pre-fetch unit comprising an instruction pre-fetch buffer to store the VLIW to await decoding by the instruction decoder, wherein the hardware register pre-fetch unit (i) pre-decodes a name of a register specified in the VLIW in advance of decoding by the instruction decoder to determine if a remote register is needed to execute the VLIW, and (ii) generates a control signal to pre-fetch data, from the specified remote register in a remote processing core or from a remote bypass network, for an instruction along one execution path in a program, in advance of decoding of the VLIW by the instruction decoder for execution, based on a compiler analysis of the program that schedules instructions that are data dependent by taking into account a latency of the inter-cluster communication bus, a size of the instruction pre-fetch buffer, and a depth of the processor pipeline.

|
Background / Summary: |
Show background / summary

|
Drawing Descriptions: |
Show drawing descriptions

|
Description: |
Show description

|
|